Suppressing high-frequency laser phase noise, particularly at frequencies near and beyond typical feedback bandwidths of a few megahertz, is a critical yet challenging task in many advanced applications. Feedforward-based methods generally outperform feedback in the high-frequency range, but their performances are more susceptible to perturbations. In this work, we focus on the Pound-Drever-Hall (PDH)-feedforward method that we demonstrated recently [Y.-X. Chao et al., Optica 11(7), 945–950 (2024)] and analyze the factors that affect its long-term stability. By constructing a simple circuit allowing for adaptive control of the feedforward gain in response to power fluctuations of cavity transmission, we demonstrate a robust $\ge 40$-dB suppression of laser phase noise around 2 MHz and a noise suppression bandwidth up to 50 MHz. In comparison, when using normal PDH feedback, robust noise suppression of over 40 dB can only occur for frequencies below tens of kilohertz in most setups. Our findings may pave the way for general usage of PDH feedforward and allow for simple construction of low-noise lasers for precise quantum control and precision metrology.

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• Laser-system design
• Noise
• Optical coherence
• Optoelectronics
• Quantum fluctuations & noise
• Quantum information with atoms & light
• Laser techniques
• Precision measurements